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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Participatory archiving: exploring a collaborative approach to Aboriginal societal provenance

Rydz, Michelle 23 September 2010 (has links)
This thesis outlines the history of thinking about provenance in the archival profession, focusing specifically on the emergence of the concept of societal provenance and its implications for Aboriginal societal memory. It presents various ways in which the archival profession is currently involved in participatory projects for the public at large and for Aboriginal communities in particular. This thesis asks the question, if records are a creation of community and society, then should not community and society be more involved in their archiving? The thesis calls on archivists to advance the practice of participatory archiving by continuing to engage in collaborative projects, to open dialogue between the archival profession and Aboriginal communities as a means of establishing relationships of trust, and to embrace ways of remembering that challenge and unsettle the traditional archival application of provenance.
62

Turquoise exchange and procurement in the Chacoan World

Hull, Sharon Kaye 18 September 2012 (has links)
The large amount of turquoise artifacts recovered from archaeological sites in the American Southwest and Mesoamerica suggests that turquoise was an important commodity in pre-Columbian trade networks. However, the spatial and temporal patterns of turquoise exchange networks and the provenance regions of the turquoise in the southwestern United States and Mesoamerica are poorly understood. Turquoise (CuAl6(PO4)4(OH)8•4(H2O)) is a supergene mineral that forms from meteoric water along fractures that are often associated with copper porphyry deposits. This copper-rich mineral can range in color and chemistry within a single sample or deposit. The ability to identify the turquoise resource areas of turquoise artifacts using the stable isotopes of hydrogen (2H/1H) and copper (65Cu/63Cu) has overcome many of the limitations of trace element analyses of complex minerals such as turquoise. The geography and geology of turquoise deposits dictate the isotopic composition of turquoise. Employing the Secondary Ion Mass Spectrometry (SIMS) technique to measure the hydrogen and copper stable isotope ratios in turquoise samples, a comparative reference database consisting of 876 analyses from 21 turquoise resource areas in the western United States was established. Sixty-two turquoise artifacts recovered from Aztec Ruin, Salmon Ruin, and nine sites in Chaco Canyon were analyzed and their isotopic signatures were compared to the reference database identifying the turquoise resource areas of 35 artifacts. These results were compared to pre-existing models of trade and exchange in the American Southwest and models that explain the complex culture history of the inhabitants of these sites. The results showed that turquoise was obtained from several different turquoise provenance regions across the western United States and there are notable differences in the turquoise procurement patterns between the three major great houses and between Pueblo Bonito and the small sites within Chaco Canyon. The results from this study improved the understanding of turquoise trade and relationships among the occupants of important Ancestral Puebloan sites in northwestern New Mexico. The development of the turquoise comparative reference database established the foundation of future research for reconstruction of ancient turquoise trade networks and investigation of turquoise procurement strategies in the American Southwest and Mesoamerica.
63

Provenance Analysis of the Sperm Bluff Formation, southern Victoria Land, Antarctica

Savage, Jeni Ellen January 2005 (has links)
Beacon Supergroup rocks of probable Devonian age, containing conglomerate clasts of lithologies unknown in outcrop in southern Victoria Land (SVL) occur in the St Johns Range to Bull Pass Region, SVL, Antarctica. The Lower Taylor Group sedimentary rocks, herein called the Sperm Bluff Formation, unconformably rest on the regionally extensive Kukri Erosion Surface that truncates local basement. The basement complex includes three Plutonic Suites, Dry Valley (DV) 1a, DVIb and DV2 of the Granite Harbour Intrusives that intrude metasedimentary rocks of the Koettlitz Group. Allibone et al. (1993b) suggested a SVL terrane accretion event may have occurred about the same time as accretion of a terrane known as the Bowers terrane in northern Victoria Land (NVL) based on changing chemistry of the CambroOrdovician granitoids. Further, it is suggested that conglomerate clasts of the Sperm Bluff Formation may have been derived from this postulated terrane (Allibone et al., 1993b; and Turnbull et al., 1994). Following extensive fieldwork provenance studies and basin analysis of the sedimentary Sperm Bluff Formation are used here to test these ideas. The Sperm Bluff Conglomerate of Turnbull et al. (1994) is re-interpreted as the Sperm Bluff Formation and described using a lithofacies-based approach. The Sperm Bluff Formation is divided into six lithofacies including 1) Conglomerate Lithofacies; 2) Pebbly Sandstone Lithofacies; 3) Crossbedded Sandstone Lithofacies; 4) Parallelbedded Lithofacies; 5) Low-angle Crossbedded Lithofacies; and 6) Interbedded Siltstone/Sandstone Lithofacies. The intimate field association of the Conglomerate, Pebbly Sandstone and Crossbedded Sandstone Lithofacies ties them to the Conglomerate Lithofacies Association whereas the other three units are independent. The Conglomerate Lithofacies Association is interpreted to represent a wavedominated deltaic environment, based on the presence of broad channels, pervasive crossbedding, paleocurrent and trace fossil data. Both Parallel-bedded and Low-angle Crossbedded Sandstone Lithofacies are interpreted as a foreshore-shore face shallow marine setting on the basis of low-angle crossbeds and trace fossil assemblages. The Interbedded Siltstone and Sandstone Lithofacies is interpreted as an estuarine environment based on alternating siltstone/sandstone beds and the presence of flaser and lenticular bedding, small crossbedded dune sets, mud drapes, syneresis cracks and diverse paleocurrent directions. An estuarine setting is tentatively favoured over a lagoonal setting due to the presence of syneresis cracks small channels and the proximity to a river delta. I suggest that the Sperm Bluff Formation is likely a lateral correlative of the Altar Mt Formation of the Middle Taylor Group, in particular the Odin Arkose Member. This interpretation is based on arkosic nature of the sedimentary rocks, regional paleocurrent patterns, the presence of salmon pink grits at Gargoyle Turrets and trace fossil assemblages. The upper most lithofacies at Mt Suess, the Low-angle Crossbedded Sandstone Lithofacies that only occurs at this site is- suggested as a lateral correlative to the Arena Sandstone, which stratigraphically overlies the Altar Mt Formation, based on quartzose composition, clay matrix, stratigraphic position and trace fossils present. Provenance analysis was carried out on sedimentary rocks and conglomerate clasts using clasts counts of conglomerates, petrographic analysis of clasts, point counts of sandstones and clasts, geochemistry and V-Pb detrital zircon analysis. Conglomerate clasts lithologies include dominantly silicic igneous clasts and finely crystalline quartzite clast amongst other subordinate lithologies such as vein quartz, schist, schorl rock, gneiss and sandstone. Despite past identification of granitoid clasts in the Sperm Bluff Formation (Turnbull et al., 1994), none were found. Rhyolitic clasts of the Sperm Bluff Formation have compositions typical of highly evolved subduction related rocks, although they have undergone post-emplacement silicification. Wysoczanski et al. (2003) date rhyolite and tuff clasts between 497±17 Ma and 492±8 Ma, placing them within error of all three Dry Valley Magmatic Suites and removing the likelihood of correlation to NVL volcanic rocks. Petrographic analysis suggests they are components of a silicic magmatic complex. Chemically the volcanic clasts appear to represent a single magmatic suite (Sperm Bluff Clast Suite), and are clearly related to the Dry Valley Plutonic Suites. Although clasts are not constrained beyond doubt to one Suite, DV2 is the best match. Quartzite clasts of the Sperm Bluff Formation are too pure and old to be derived from a local source. Detrital zircon V-Pb ages for the quartzite suggest zircons were derived from the East Antarctic Craton, and that the quartzite source rocks were deposited prior to the Ross-Delamarian Orogeny. Quartzite with a similar age signature has not been identified; however, the Junction Formation sandstone of northwest Nelson has a similar age spectrum. Sandstones from the Sperm Bluff Formation indicate derivation from a felsic continental block provenance, which contain elements of volcanic, hyperbyssal and plutonic rocks. They are arkosic to quartzose in composition and conspicuously lack plagioclase. Detrital zircon analyses give a strong 500 Ma peak in all 3 samples, characteristic of a Ross-Delamarian Orogen source, with few other peaks. The dominance of a single peak is highly suggestive oflocal derivation. The sedimentary rocks of the Sperm Bluff Formation are interpreted to be derived predominantly from the basement rocks they now overlie. The presence of the regionally extensive Kukri Erosion Surface at the lower contact of the Beacon Supergroup rocks implies an intermediate source must have existed. This most likely contained all components of the formation. I suggest that the DV2 Suite was emplaced in a subsiding, extensional intra-arc setting. Erosion of the uplifted arc region probably occurred from Late Ordovician to Silurian times with deposition of sediments in a subsiding intra-arc basin. Erosion of the rhyolitic complex in this region probably occurred, however, it is likely that some was preserved. Inversion of this basin prior to the Devonian probably provided the means for these sediments to be deposited as the Sperm Bluff Fonnation.
64

Paleoenvironmental Interpretations of the Lower Taylor Group, Olympus Range area, southern Victoria Land, Antarctica

Gilmer, Greer Jessie January 2008 (has links)
The Devonian Taylor Group, in the Olympus Range area, southern Victoria Land (SVL), Antarctica, is separated from the basement by a regional nonconformity (Kukri Erosion Surface). A second localized unconformity within the Taylor Group called the Heimdall Erosion Surface separates the New Mountain Sandstone and older units from the younger Altar Mountain Formation. The depositional environment of the New Mountain Sandstone has long been under contention. The New Mountain Sandstone Formation is a predominantly quartzose cross-bedded sandstone. Its newly defined Mt Jason Member is a coarse arkosic small scale cross-bedded pebbly sandstone that grades up section into the rest of the quartzose New Mountain Sandstone with large scale cross beds. The New Mountain Sandstone has been divided into five lithofacies including the Basal Conglomerate Lithofacies, Pebbly Sandstone Lithofacies, Granule Cross-bedded Lithofacies, Pinstripe Cross-bedded Lithofacies and Cross-bedded Sandstone Lithofacies. Deposition was in a shoreface environment with minor coastal aeolian deposition. The environment changed from upper shoreface to lower shoreface up section, forming transgressive to highstand systems tracts. The Heimdall Erosion Surface truncates the Cross-bedded Sandstone Lithofacies and the Pinstripe Cross-bedded Lithofacies and was formed due to relative sea level fall leading to exposure and erosion of underlying sedimentary and basement rocks. It forms a type 1 sequence boundary. The New Mountain Sandstone was partially or totally lithified before erosion as shown by the jagged morphology of the eroded cross beds on the surface. It is not known when cementation of the NMS took place or how much of the formation has been eroded. The Heimdall Erosion Surface and Kukri Erosion Surface converge locally due to erosion on the Heimdall Erosion Surface and relief on the Kukri Erosion Surface. The Heimdall Erosion Surface became a shore platform and the site of deposition as relative sea level rose. The Altar Mountain Formation with its Odin Member is a cross-bedded, massive and bedded feldspathic and quartzose sandstone that fines up section and is deposited on the erosion surface. The Altar Mountain Formation is divided into four lithofacies including the Conglomerate Lithofacies, Trough Cross-bedded Lithofacies, Cross-bedded Bioturbated Lithofacies and Bedded Fine Lithofacies. Deposition was in a shoreface environment, changing up section to an inner shelf environment with minor estuarine/tidal influence near the top of the section forming transgressive to highstand to regressive system tracts. The sedimentary rocks are derived mainly from the Granite Harbour Intrusives and Koettlitz Group, which underlie the sandstones, but were exposed elsewhere in SVL. The sandstone clasts within the Conglomerate Lithofacies could be derived from underlying older Taylor Group rocks or exotic sources from outside the field area. Correlation with data from adjacent areas suggests deposition of the New Mountain Sandstone occurred in a shallow sea that existed from the Olympus Range, southwards into the Asgard Range and included Vashka Crag. The area around Sponsors Peak and to the north was exposed and supplying feldspathic and quartzose sediment and pebbles into the depositional basin. As relative sea level fell due to either tectonic uplift or eustatic processes a large area of southern Victoria Land was exposed including the Olympus and Asgard Ranges and Bull Pass-St Johns Range area. This lead to erosion of the New Mountain Formation and basement rocks. Deposition of the New Mountain Sandstone continued further south shown by the gradational contact between it and the overlying Altar Mountain Formation. Relative sea level rise led to deposition of the Altar Mountain Formation. Shallow seas once more dominated the southern Victoria Land with deltas in the east (in the Bull Pass-St Johns Range area) feeding feldspathic sediment into the depositional basin (Odin Member). Further sea level rise drowned the delta region and a shallow marine to inner shelf environment led to deposition of the rest of the Altar Mountain Formation.
65

Variation in common lime (Tilia x europaea L.) in Swedish Gardens of the 17th and 18th centuries /

Bengtsson, Rune, January 2005 (has links) (PDF)
Diss. Alnarp : Sveriges lantbruksuniversitet, 2005.
66

STABLE ISOTOPE RATIOS AS A PROXY FOR HUMAN GEOGRAPHIC PROVENANCE: BIOGEOGRAPHICAL EVIDENCE FROM THE 2H, 18O, AND 13C SIGNATURES IN MODERN HUMAN TEETH

Holobinko, Anastasia 01 December 2015 (has links)
The positive identification of a decedent is paramount to a forensic investigation in which human remains have been recovered and must be identified. Due to increasing global mobility in the world's populations, it is not inconceivable that an individual might die far away from his or her home. Pinpointing an individual's geographic origin may contribute to definitive forensic identification of contemporary human skeletal remains in cases where dental records and other means of identification are either unavailable to law enforcement personnel or do not yield immediate results. Stable isotope analysis of biogenic tissues such as tooth enamel and bone mineral has become a well‐recognized and increasingly important method for determining the provenance of human remains, and it has been used successfully in bioarchaeological studies as well as forensic investigations. Both 18O and 2H stable isotope signatures are well established proxies as environmental indicators of climate (temperature) and source water and are therefore considered reliable indicators of geographic life trajectories of animals and humans. Similarly, 13C and 15N abundance data have distinguished dietary preferences in ancient human populations, and have been used to qualify 2H and 18O geolocational data that may be consistent with more than one location. Few if any studies have systematically investigated the multi-isotopic signatures in human tooth enamel and dentin from living individuals. Since 18O abundance values obtained from tooth enamel of late-erupting molars are a source of information on geographic origin of an individual during adolescence when crown formation takes place, it was hypothesized that: 1) the stable isotope abundance of 2H, 18O, and 13C in human tooth enamel and dentin is consistent with self-reported residential history and dietary preferences data, and 2) the isotopic variability evident between individuals with shared residential history and nutrient intake is quantifiable, and indicative of intra-individual variability. Two pilot studies were conducted to: 1) evaluate the feasibility of extracting and measuring the 2H composition of human tooth enamel and its suitability as a proxy for human geographic provenance, and 2) compare the isotopic abundance of isotopic abundance of 2H and 13C in human crown dentin collagen obtained from archaeological and modern teeth with the 18O and 13C isotopic composition of the corresponding tooth enamel carbonate. A protocol for preparing tooth enamel for 2H analysis was successfully devised and implemented; however, no correlation was observed between tooth enamel 2H abundance values as measured plotted against source water 2H abundance values. While unexpectedly low rates of hydrogen exchange within mineral hydroxyl groups were documented, and it was possible to analyze tooth enamel for its 2H isotopic composition, the seemingly fixed nature of 2H abundance in tooth enamel means that the 2H isotopic signature of tooth enamel cannot be used as an indicator of geographic provenance. Conversely, positive correlations between collagen 2H abundance values of primary dentin with 2H abundance values for source water and also with enamel 18O abundance values suggests that primary dentin collagen 2H values are linked to the isotopic composition of source water. Third molar tooth enamel was sampled from 10 living volunteers undergoing routine tooth extractions at University of Toronto affiliated dental clinics in Ontario, Canada. The mixed-sex group of patients was given questionnaires in which they provided detailed residential history and answered questions pertaining to dietary preferences (e.g., vegetarian) prior to donating all four third molars. Enamel was drilled from the crown of two third molars from each subject, chemically cleaned, and subjected to an acid digest before being analyzed for its 18O and 13C composition using Isotope Ratio Mass Spectrometry. Herewith, isotope abundance values are presented using the delta notation as delta values in per mil (‰). Mean d13CVPDB values for all samples ranged from -9.47 ‰ to -11.31 ‰ (pooled mean = -10.37 ‰), which suggested a persistent C4 plant dietary influence at the time the sampled tooth enamel was forming and is consistent with the typical North American diet. While inter-subject variation contributed the largest proportion of total d13C variability, differences were not significant. The pooled mean d18OVSMOW value for enamel samples was 24.39 ‰, while individual subject mean d18OVSMOW values ranged from 23.76 ‰ to 25.18 ‰. Marked offsets (0.01 ‰ - 0.51 ‰) in mean d18OVSMOW values for each pair of third molars were observed. While subject variation was significant (p=0.0034), neither diet nor sex significantly influenced the oxygen (or carbon) isotope data. Following conversion of d18OVSMOW values to d18OPhosphate values, drinking water values were calculated using the Daux et al. (2008) equation, and compared to their corresponding regional estimated annual average d18O values in precipitation retrieved from the Online Isotopes in Precipitation Calculator (OIPC) (Bowen 2014). Despite observed correlations between the drinking water d18OWater values and d18OOIPC values of four subjects, no statistically significant correlations were evident between the two limited data sets. However, when the isotopically similar d18O values of Toronto area residents were averaged and combined with the remaining Canadian data and the 18O data from 5 enamel samples analyzed in the 2H enamel pilot study, strong positive correlations were evident between d18OPhosphate valuesand d18OOIPC values (R2 = 0.87). Moreover, an equally strong linear relationship was observed between modeled annual precipitation 18O and calculated source water 18O (R2 = 0.87). Based on the d2H, d18O, and d13C values measured in tooth enamel and dentin, it is possible to infer and confirm geographic provenance and dietary intake. However, while enamel carbonate d13C values were consistent with self-reported dietary intake information and residential history, as could be expected vegetarians could not be distinguished from those who consumed meat without determining C/N isotopic ratios in dentin collagen. Further, the presence of strong linear relationships between the 18O composition of enamel carbonate and modeled source water 18O in the merged dataset illustrates the importance of considering site-specific isotopic complexities and using multi-isotope data obtained from multiple tissues when investigating the geographic origins of humans in an archaeological or forensic context. It is not possible to quantify intra-individual isotopic variability without sampling from larger, geographically diverse populations and controlling for as many variables as possible. The construction of regional databases containing 18O and 2H isotopic data obtained from a variety of environmental and human and faunal tissue samples, and the application of such data to individual cases in which geographic origins are desired, is recommended provided the following caveats are considered: 1) whenever possible, d18OPhosphate values should be used when comparing d18O values in tooth enamel with those in precipitation in order to avoid the unmitigated error associated with the application of carbonate conversion equations to enamel phosphate d18O data, 2) the continuous consumption of food sourced elsewhere is liable to affect the overall enamel carbonate d18O values, 3) d18O values in precipitation are not inclusive of the variety of postprecipitation and hydrological processes unique to a particular location, nor are they an accurate representation of the isotopically mixed nature of tap water sourced from distant reservoirs. Hence, extrapolations should be made with caution. Enamel sequential microsampling methods may be advisable for narrowing down a geographic timeline if the overlapping of isotopic signals at various points along the tooth’s longitudinal plane can be quantified and validated. While standardization of analytical methodology is critical to appropriate interpretations of the data, stable isotope profiling is not a standalone method and should be used in conjunction with other lines of evidence in determinations of human provenance.
67

Geologia isotópica e geocronologia do complexo metamórfico porongos e suíte metamórfica várzea do capivarita, Cinturão Dom Feliciano, Sul do Brasil: i implicações para a evolução do Gondwana em sua margem ocidental

Gruber, Leonardo January 2016 (has links)
Proveniência por métodos isotópicos em duas unidades litodêmicas – o Complexo Metamórfico Porongos (CMP) no domínio central-oriental do Cinturão Dom Feliciano (CDF) e a Suíte Metamórfica Várzea do Capivarita (SMVC), localizada no domínio leste do CDF - apresentou áreas-fonte similares nos dois casos: Os metassedimentos do CMP, na região das Antiformes de Santana da Boa Vista e Serra dos Pedrosas, foram depositados entre 785 e 595 Ma (U-Pb em zircão detrítico por LA-ICP-MS). Apresentam registros de áreas-fonte com predominância de idades de ca. 2.2 – 2.0 Ga, mesmas idades do embasamento da região, o Complexo Encantadas. As assinaturas isotópicas de 207Pb/204Pb X 206Pb/204Pb mostraram pouca relação dos metassedimentos do CMP com áreas-fonte do cráton Rio de La Plata, e εNd variando entre -13 a -6.5, com valores menos negativos para amostras onde foram obtidos zircões com mesma idade do vulcanismo félsico do CMP. Outros registros incluem idades de 1.5-1.4 Ga, cujas assinaturas εHf indicam fontes juvenis, possivelmente relacionadas a um sistema de rifteamento registrado nos Anortositos Capivarita. Na Antiforme Capané, zircões datados em SHRIMP e LA-ICP-MS de rochas metavulcânicas intermediárias a félsicas indicaram idades de 663 ± 2.7 Ma, representando um vulcanismo mais jovem do que aquele encontrado anteriormente no CMP, vinculado à fusão parcial crustal. Novos dados U-Pb em zircão confirmam registro do metavulcanismo de 783.4 ± 3.9 Ma nos metassedimentos, comparáveis a idades obtidas nos Gnaisses Cerro Bori, interpretados como um arco continental de ca. 800 Ma. Zircões detríticos de rochas metassedimentares da SMVC apresentaram registros de ca. 2.2 – 2.0 Ga, além de idades de ca. 1.4 Ga e idade máxima de deposição de 714.3 ± 3.9 Ma, com pico metamórfico registrado em borda metamórfica de zircões com 618 ± 7.3 Ma εHf predominantemente negativas. Mármores apresentaram razões 87Sr/86Sr de 0.70609, o que permite deduzir uma idade de deposição mais antiga que 715 Ma, próximo dos valores encontrados em mármores na região de Arroio Grande. A comparação dos isótopos de Hf com rochas do Cinturão Damara nos crátons Kalahari e Congo, cuja amalgamento junto ao Rio de La Plata deu origem ao Gondwana Ocidental, mostram que existe pouca ou nenhuma relação com áreas-fonte dos metassedimentos do CMP e SMVC no Neoproterozóico. Estes dados levam a dedução de que acresção de terrenos ou microcontinentes com características de embasamento, nesse caso denominado aqui como Embasamento Encantadas, cuja evolução se dá com acresção de um arco continental de idades entre 780 e 660 Ma, é a origem de parte das áreas-fonte do CMP, e possivelmente foi um dos eventos tectônicos que controlaram evolução do terreno ao longo do CMP e SMVC. / Isotopic provenance realized in two lithodemic units – Porongos Metamorphic Complex (PMC), in the central-eastern domain of the Dom Feliciano Belt (DFB) and the Várzea do Capivarita Metamoprhic Suite (VCMS), in the eastern domain of the same belt – presented similar source-areas in both cases: The PMC metasediments, in Santana da Boa Vista and Serra dos Pedrosas Antiforms were deposited between 785 and 595 Ma (LA-ICP-MS detrital zircon U-Pb). Both PMC and VCMS displayed source-areas with ages varying from ca. 2.2 – 2.0 Ga, which is the same age presented in the regional basement, the Encantadas Complex. 207Pb/204Pb X 206Pb/204Pb isotopic signatures displayed little resemblance between CMP metasediments and possible source-areas in the Rio de La Plata Craton, and εNd varied between -13 to -6.5, with less negative values in samples were where obtained zircons with the same age of felsic volcanism in the PMC. Others records included ages from 1.5 to 1.4 Ga, with εHf signatures indicating juvenile sources, possibly related to a rifting system recorde in the Capivarita Anorthosite. In the Capané Antiform, SHRIMP and LA-ICP-MS U-Pb zircon ages from felsic to intermediary metavolcanic rocks displayed 663 ± 2.7 Ma, which is a younger record than the previously obtained in the PMC, and can be related to partial crustal fusion. Also new U-Pb detrital zircon ages confirm the record of the metavolcanics of 783.4 ± 3.9 Ma in the metasediments, comparable to the ages obtained in the Cerro Bori orthogneisses, interpreted as a continental arc of ca. 800 Ma. Metasedimentary rocks of VCMS displayed zircons with ca. 2.2-2.0 Ga, besides ages of ca. 1.4 Ga and maximum depositional age of 714.3 ± 3.9 Ma, with metamorpich peak recorded in metamorphic rims of 618 ± 7.3 Ma and negative εHf signatures. Marbles presented 87Sr/86Sr ratios of 0.70609, which can be deducted as an older than 715 Ma depositional age, near values obtained to Arroio Grande marbles. Comparison of Hf signatures with rocks from Damara Belt of Kalahari and Congo Cratons, whose assembly with Rio de La Plata to form West Gondwana in Neoproterozoic, displayed little to no relationship with the source-areas of PMC and VCMS metasediments I in the Neoproterozoic. This indicates that terrain or a microcontinent accretion with basement features, in this case the Encantadas Basement, whose evolution underwent accretion in a continental arc between 780 to 660 Ma, it’s the source to part of the PMC , and possible was one of the tectonic events that controlled terrain evolution in the PMC and VCMS.
68

Understanding Legacy Workflows through Runtime Trace Analysis

January 2015 (has links)
abstract: When scientific software is written to specify processes, it takes the form of a workflow, and is often written in an ad-hoc manner in a dynamic programming language. There is a proliferation of legacy workflows implemented by non-expert programmers due to the accessibility of dynamic languages. Unfortunately, ad-hoc workflows lack a structured description as provided by specialized management systems, making ad-hoc workflow maintenance and reuse difficult, and motivating the need for analysis methods. The analysis of ad-hoc workflows using compiler techniques does not address dynamic languages - a program has so few constrains that its behavior cannot be predicted. In contrast, workflow provenance tracking has had success using run-time techniques to record data. The aim of this work is to develop a new analysis method for extracting workflow structure at run-time, thus avoiding issues with dynamics. The method captures the dataflow of an ad-hoc workflow through its execution and abstracts it with a process for simplifying repetition. An instrumentation system first processes the workflow to produce an instrumented version, capable of logging events, which is then executed on an input to produce a trace. The trace undergoes dataflow construction to produce a provenance graph. The dataflow is examined for equivalent regions, which are collected into a single unit. The workflow is thus characterized in terms of its treatment of an input. Unlike other methods, a run-time approach characterizes the workflow's actual behavior; including elements which static analysis cannot predict (for example, code dynamically evaluated based on input parameters). This also enables the characterization of dataflow through external tools. The contributions of this work are: a run-time method for recording a provenance graph from an ad-hoc Python workflow, and a method to analyze the structure of a workflow from provenance. Methods are implemented in Python and are demonstrated on real world Python workflows. These contributions enable users to derive graph structure from workflows. Empowered by a graphical view, users can better understand a legacy workflow. This makes the wealth of legacy ad-hoc workflows accessible, enabling workflow reuse instead of investing time and resources into creating a workflow. / Dissertation/Thesis / Masters Thesis Computer Science 2015
69

Geologia isotópica e geocronologia do complexo metamórfico porongos e suíte metamórfica várzea do capivarita, Cinturão Dom Feliciano, Sul do Brasil: i implicações para a evolução do Gondwana em sua margem ocidental

Gruber, Leonardo January 2016 (has links)
Proveniência por métodos isotópicos em duas unidades litodêmicas – o Complexo Metamórfico Porongos (CMP) no domínio central-oriental do Cinturão Dom Feliciano (CDF) e a Suíte Metamórfica Várzea do Capivarita (SMVC), localizada no domínio leste do CDF - apresentou áreas-fonte similares nos dois casos: Os metassedimentos do CMP, na região das Antiformes de Santana da Boa Vista e Serra dos Pedrosas, foram depositados entre 785 e 595 Ma (U-Pb em zircão detrítico por LA-ICP-MS). Apresentam registros de áreas-fonte com predominância de idades de ca. 2.2 – 2.0 Ga, mesmas idades do embasamento da região, o Complexo Encantadas. As assinaturas isotópicas de 207Pb/204Pb X 206Pb/204Pb mostraram pouca relação dos metassedimentos do CMP com áreas-fonte do cráton Rio de La Plata, e εNd variando entre -13 a -6.5, com valores menos negativos para amostras onde foram obtidos zircões com mesma idade do vulcanismo félsico do CMP. Outros registros incluem idades de 1.5-1.4 Ga, cujas assinaturas εHf indicam fontes juvenis, possivelmente relacionadas a um sistema de rifteamento registrado nos Anortositos Capivarita. Na Antiforme Capané, zircões datados em SHRIMP e LA-ICP-MS de rochas metavulcânicas intermediárias a félsicas indicaram idades de 663 ± 2.7 Ma, representando um vulcanismo mais jovem do que aquele encontrado anteriormente no CMP, vinculado à fusão parcial crustal. Novos dados U-Pb em zircão confirmam registro do metavulcanismo de 783.4 ± 3.9 Ma nos metassedimentos, comparáveis a idades obtidas nos Gnaisses Cerro Bori, interpretados como um arco continental de ca. 800 Ma. Zircões detríticos de rochas metassedimentares da SMVC apresentaram registros de ca. 2.2 – 2.0 Ga, além de idades de ca. 1.4 Ga e idade máxima de deposição de 714.3 ± 3.9 Ma, com pico metamórfico registrado em borda metamórfica de zircões com 618 ± 7.3 Ma εHf predominantemente negativas. Mármores apresentaram razões 87Sr/86Sr de 0.70609, o que permite deduzir uma idade de deposição mais antiga que 715 Ma, próximo dos valores encontrados em mármores na região de Arroio Grande. A comparação dos isótopos de Hf com rochas do Cinturão Damara nos crátons Kalahari e Congo, cuja amalgamento junto ao Rio de La Plata deu origem ao Gondwana Ocidental, mostram que existe pouca ou nenhuma relação com áreas-fonte dos metassedimentos do CMP e SMVC no Neoproterozóico. Estes dados levam a dedução de que acresção de terrenos ou microcontinentes com características de embasamento, nesse caso denominado aqui como Embasamento Encantadas, cuja evolução se dá com acresção de um arco continental de idades entre 780 e 660 Ma, é a origem de parte das áreas-fonte do CMP, e possivelmente foi um dos eventos tectônicos que controlaram evolução do terreno ao longo do CMP e SMVC. / Isotopic provenance realized in two lithodemic units – Porongos Metamorphic Complex (PMC), in the central-eastern domain of the Dom Feliciano Belt (DFB) and the Várzea do Capivarita Metamoprhic Suite (VCMS), in the eastern domain of the same belt – presented similar source-areas in both cases: The PMC metasediments, in Santana da Boa Vista and Serra dos Pedrosas Antiforms were deposited between 785 and 595 Ma (LA-ICP-MS detrital zircon U-Pb). Both PMC and VCMS displayed source-areas with ages varying from ca. 2.2 – 2.0 Ga, which is the same age presented in the regional basement, the Encantadas Complex. 207Pb/204Pb X 206Pb/204Pb isotopic signatures displayed little resemblance between CMP metasediments and possible source-areas in the Rio de La Plata Craton, and εNd varied between -13 to -6.5, with less negative values in samples were where obtained zircons with the same age of felsic volcanism in the PMC. Others records included ages from 1.5 to 1.4 Ga, with εHf signatures indicating juvenile sources, possibly related to a rifting system recorde in the Capivarita Anorthosite. In the Capané Antiform, SHRIMP and LA-ICP-MS U-Pb zircon ages from felsic to intermediary metavolcanic rocks displayed 663 ± 2.7 Ma, which is a younger record than the previously obtained in the PMC, and can be related to partial crustal fusion. Also new U-Pb detrital zircon ages confirm the record of the metavolcanics of 783.4 ± 3.9 Ma in the metasediments, comparable to the ages obtained in the Cerro Bori orthogneisses, interpreted as a continental arc of ca. 800 Ma. Metasedimentary rocks of VCMS displayed zircons with ca. 2.2-2.0 Ga, besides ages of ca. 1.4 Ga and maximum depositional age of 714.3 ± 3.9 Ma, with metamorpich peak recorded in metamorphic rims of 618 ± 7.3 Ma and negative εHf signatures. Marbles presented 87Sr/86Sr ratios of 0.70609, which can be deducted as an older than 715 Ma depositional age, near values obtained to Arroio Grande marbles. Comparison of Hf signatures with rocks from Damara Belt of Kalahari and Congo Cratons, whose assembly with Rio de La Plata to form West Gondwana in Neoproterozoic, displayed little to no relationship with the source-areas of PMC and VCMS metasediments I in the Neoproterozoic. This indicates that terrain or a microcontinent accretion with basement features, in this case the Encantadas Basement, whose evolution underwent accretion in a continental arc between 780 to 660 Ma, it’s the source to part of the PMC , and possible was one of the tectonic events that controlled terrain evolution in the PMC and VCMS.
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Analysis Of The Mineral Composition Of The Ceramic Vessels From Puerto Nuevo: Some Preliminary Considerations Regarding Production And Provenance / Análisis de la composición mineral de las vasijas de cerámica de Puerto Nuevo: algunas consideraciones preliminares sobre su producción y procedencia

Druc, Isabelle, Dulanto, Jalh, Rey de Castro, Alejandro, Guadalupe, Enrique 10 April 2018 (has links)
The analysis of ceramic fragments from the site of Puerto Nuevo (1000-500 AC), on the south coast of Peru, reveals a diversified ceramic production and possible long distance interaction networks for ceramics along the coast during the first half of the first millennium before our era. Macroscopic analysis with a hand-held digital low power microscope of fresh cross-sections conducted by Alejandro Rey de Castro allowed classifying the ceramics in different paste groups as well as identifying atypical ceramics. Petrographic analysis conducted by Isabelle Druc on 120 ceramic thin sections of these fragments helped refine this classification into six compositional groups, providing more details on the production and provenance of the wares. Comparison with 30 thin sections of clay-tiles collected in the lower and middle valley of the Ica and Pisco Rivers and on the littoral between the two rivers, showed that a majority of ceramics was manufacturedwith local sediments without much sorting. Different resource areas were exploited around Puerto Nuevo, on the littoral and in the Lower and Middle Ica and Pisco valleys. Based on these results, we propose the existence of severalcommunities of potters working in the Puerto Nuevo region. One (or more) of these communities must have used coastal sandy clays with no need to ad temper, another mined inland clay deposits with natural inclusions of charophyte algae, and other(s) used materials rich in granodioritic rock fragments. Thirteen atypical ceramics were singled out based on different composition, texture, or firing, suggesting other production modes. Their composition, however, still suggests a coastal provenance, indicating that the interaction network extended along the coast, rather than with the highlands. / El análisis de fragmentos de vasijas de cerámica del sitio de Puerto Nuevo (1000 a 500 a.C.), en la costa sur del Perú, revela la existencia de una producción diversificada y la probable existencia de redes de intercambio a larga distancia de vasijas de cerámica a lo largo de la costa durante la primera mitad del primer milenio antes de nuestra era. El examen macroscópico con lupa digital sobre cortes frescos realizado por Alejandro Rey de Castro permitió agrupar inicialmente los fragmentos en diferentes grupos de pasta, así como identificar varios fragmentos atípicos. A partir del análisis petrográfico de 120 láminas delgadas de estas cerámicas, Isabelle Druc refinó esta agrupación inicial en seis grupos de composición que brindan informaciones más detalladas sobre la producción y la procedencia de las vasijas de cerámica de las cuales provienen estos fragmentos. El análisis petrográfico de estas 120 láminas delgadas de fragmentos de cerámicas con 30 láminas delgadas de muestras de arcilla de los valles bajo y medio de los ríos Ica y Pisco, y del área de litoral entre lasdesembocaduras de ambos evidencia que la mayoría de las vasijas de cerámica estudiadas fueron producidas con sedimentos locales sin mucha selección granulométrica. Diversas fuentes de materias primas fueron explotadas, tanto en el área de litoral alrededor de Puerto Nuevo, como en los valles bajo y medio de los ríos Ica y Pisco. A partir de estos resultados, proponemos la existencia de varias comunidades de alfareros que trabajaban en la región de Puerto Nuevo —al menos, una caracterizada por el uso de una arcilla arenosa a la que no se agregaba temperante; otra, por el uso de una arcilla rica en algas carofitas; y otra a la que se le agregaba un temperante granodiorítico—. Trece fragmentos de vasijas de cerámica petrográficamente atípicos —con una composición, textura o cocción distintas a las de los grupos identificados para Puerto Nuevo— sugieren la existencia de otros modos de producción, mientras que el hecho de que en todos estos casos la composición sea de tipos costeños podría indicar la existencia de redes de intercambio de vasijas de cerámica preferentemente a lo largo de la costa, en lugar de entre la costa y la sierra.

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